Is there any way to prevent a " (as in inches) from being converted into a curved quotation mark in a text box?
Google told me It’s a Mac thing.
Mac System preferences > Keyboard > Text tab,
uncheck the “Use smart quotes and dashes” option.
Thanks, sorry I was blaming Rhino. 
It’s one of those weird “Mac” things.
I had to Google it to figure it out.
Furthermore: having turned off macOS’s automatically turning straight double quotes into curved (openning or closing) double quotes, if you would like to insert a curved double quote, you can do so using these key combinations:
- Opening double quote: alt + [
- Closing double quote: alt + shift + [
Also:
- Opening single quote: alt + ]
- Closing single quote: alt + shift + ]